Valve actuating mechanism



Sept. 18, 1945. L. R. SPENCER VALE ACTUATING MECHANISM Filed Sept. 18, 1944 10018 R- SPENCER Patented Sept. 18, 1945 UNITED VALVE Ac'r A'rINGMEcHANIsM Louis R.- Spencer, West Hartford, Conn assignor to Spencer Aircraft'Motors, Inc.', Hartford, Conn, a corporation of Connecticut Application This invention relates to improvements in valve actuating mechanisms wherein a cam actuated rocker arm engages a valve stem for effecting reciprocatory motion of said stem and particularly to that type of construction wherein the rocker arm is provided with a renewable Wear member in the form of a rockable disk journaled in a recess therein at a point to engage the valve stem. v

The primary object is to provide a construction of this type in which the recess in which said disk is journaled in the arm can be expeditiously bored, ground orlapped. 1 Q

Another object is to provide a construction which will expedite removal and replacement [of said valve stem engaging diskand adjustmentof valve clearances by reason of the'fact that such removal and replacement of the; disk and adjustment of the valve clearances can be accomplished without withdrawal of theactu'ator assembly from therocker arm box.

More specifically the invention contemplates a construction wherein the valve stem engaging disk can be inserted in,or removed from, its recess in the rocker arm by an axial movement through the side of the rocker arm and a further object is to provide means for normally preventing this axial displacement of said disk. A still further object is to provide a construction of the type indicated wherein rotational movement of the disk in the rocker arm is'limited by the same means which prevent axial displacement of the disk from its recess in the rocker arm.

With these and other objects in view, the invention consists in certain details of construction and combinations and arrangements of parts, all as will hereinafter be more fully explained and the novel features thereof particularly pointed out in the appended claims.

IiTthe accompanying drawing- Figure 1 is a vertical sectional view througha valve stem rocker arm of a valve actuating mechanism illustrating the preferred embodiment ofthe present invention;

Fig. 2 is a vertical sectional viewon the line 2-2 of Fig. 1; l l l Fig. 3 is a top plan view of the end of the rocker arm which engages the valve stem;

Fig. 4 is a side elevational view of the valve stem engaging disk;

Fig. 5 is an enlarged view, partly section and partly broken away, of the disk lockingmember; and

September 18, 1944, Serial No.554,689

Claims. (01. 74-519) Fig. 6 is a perspective view of said locking member. V

The valve actuating mechanism shown herein for purposes of illustrating the presentinvention is more fully shown and described in United States Letters Patent No. 2,322,173. It consists generally of a rocker arm Ill for each valve stem H, said rocker arm being pivoted at one end on a hollow pivot pin I2 and provided at its opposite end with a disk 13 journaled for rocking motion in a recess in said arm in position to bear against the upper end of the valve stem II. A cam roller I4, rotatably seated in the upper face of the rocker arm is engaged by a cam I5 on cam shaft. I6 for depressing the arm and valve stem in opening the valve (not shown) and the latter is returned to its seat or closed position by springs i"! surrounding the valve stem immediately beneath an enlargement [8 on said stem, it being {understood said springs are compressed each time the valve stem is depressed, Lubricant for the various bearing surfaces is supplied from the hollowpivot pin l2 through passage 19 in the rocker arm to the recess in which the disk 13 is journaled. By means of intersecting ducts 20, 2] in said disk-and-duct 22 in the arm, lubricant is distributed from the disk recess to the contacting surfaces of the disk and valve stem and to the recess in which cam roller I4 is journaled.

In the structure illustrated in said Patent No. 2,322,173, the valve stem engaging'disk is insertable into its recess in the rocker arm from the bottom face of the latter, due to the recess opening being wider than the reduced Width or diameter of the disk at the point where the latter is flattened to form the stem engaging surface on the pe iphery of the disk. In other words, in said patented structure, the disk is seated in a recess closed at its ends or at thesides of the rocker arm with the resultthat the machine operations required in shaping and properly finishing this closed-end recess have proven rather difficult and, obviously, expensive. In accordance with the present invention, therefore, this recess for the valve stem engagingdisk is made to expose the end of the disk at theside of therocker arm 50 as to permit the disk to be inserted or removed axially through the side of said arm. Preferably, in order to facilitate the boring and finishing of said recess it extendstransversely entirely across the rocker arm so as to expose both ends of the disk at opposite sides of the arm as best illustrated in Figs. 2 and'3. -In other words, in the preferred embodimentof the invention, thedisk'extends whose side portions constitute retainer bars 23' positioned across the open ends of the recess and the exposed ends of the disk. -It is also preferred that these retainer bars be yieldingly locked in their disk retaining positions and this may be accomplished by pivotally supporting the otherwise free ends of the bars on a cross piri 24. in the rocker arm and forming the cross-piece 25 of said U-shaped member with a spring catch 26, adapted to engage an undercut surface 21 on the end. of the rocker arm which normally prevents upward movement of said retainer bars 23, at least to an extent where they will clear the ends of the disk.

As willzbe apparent, the disk l3 must be free to rock in its recess as the rocker arm is alternately depressed and elevated. Also, prior to installation of the rocker arm in the assembly of the entire mechanism, it is essential that the disk be retained in its recess with'its flat, stem engaging surface properly disposed'at the'exterior of the rocker arm. In other words, to facilitate in stallation of the rocker'arm, care must be taken to prevent the disk turning in its recess to a point where its flattened surface'will be located Within the recess or where the disk might drop out the recess. Likewise, the rocking motion of the disk should also be limited during operation of the valve actuating mechanism. For these reasons; thedisk is provided at one or both of its ends with 'means'adapted to engage one or both of the retainer'bars 23. For instance an abutment, preferably in'the form of a shoulder 28 on theend of the disk normally spaced a'slight distance from the retaine bar will permit ample rocking motion of the disk under normal operating condi supported in its recess independently of said retainer bars. 7

2. A valve actuating mechanism comprising a pivoted rocker arm having a valve stem engaging disk journaled therein characterized 'by said arm having a disk receiving recess extending entirely across its lower surface, with the ends of the disk exposed at opposite sides of the arm, retainer bars pivotally mounted on each side of said arm and movable to and from positions across the ends of said recess and disk, and means for releasably locking said bars across the ends of aid recess and disk.

3. A valve actuating mechanism comprising a pivoted rocker arm having a valve stem engaging disk journaled therein characterized by said arm having a disk receiving recess extending entirely tions but, at the same time, such rocking'motionwill be limited by the abutment or shoulder engaging the retainer bar. v

Thus the present invention provides a structure wherein the disk recess can be expeditiously and comparatively inexpensively formed and machine finished; the disk can be readily inserted in its recess and securely retained therein at all times while still being allowed ample rocking motion under operating conditions; and the disk can just as quickly be removed by releasing the retainer bar catch 26 and elevating said'barsto permit withdrawal of the disk endwise'through' the side of the rocker arm.

What I claim is:

1. A valve actuating mechanism comprising a rocker arm having a valve stem engaging disk journaled therein, characterized by said arm having a disk receiving recess extending transversely therethrough in which the disk is rotatably supported with the ends of the disk exposed atopposite sides of the arm, removable retainer bars carried on said arm and normally. positioned across the ends of said recess atopposite' sides of said arm, and means for releasablylocking; said bars; in their normal position, said disk being rotatably across its lower surface, with the ends of the disk exposedat opposite sides of the arm, retainer bars pivotally mounted on each side of said arm and movable to and from positions across the ends of said recess and disk, and a cross-piece connecting said retainer bars frictionally engaging the free end of the rocker arm for releasably locking said bars across the ends of the recess and disk.

4. A valve actuating mechanism comprising a pivoted rocker arm having a valve stem engaging disk journaled therein characterized bysaid arm having an undercut surface on one face thereof and a transverse disk receiving recess extending entirely across the same with the endsof the disk exposed at opposite sides of the arm, retainer bars pivoted on opposite sides of the rocker arm and movable to and from positions across the exposed ends of the disk and spring means attached to said bars engageable with said undercut surface for releasably locking said retainer bars in position across the ends of said disk.

' 5. A valve stem actuating mechanism comprising a rocker arm having a valve stem engaging disk journaled therein characterized by said arm having an undercut end face and a transverse disk receiving recess extending entirely across the same with the ends of the disk exposed at opposite sides of the arm, and a U-shaped disk retainer having its side members pivoted on the sides of the rocker arm and movable to and from positions across the exposed ends of the'disk and a spring on its cross member engageable with the undercut end surface of the rocker arm for releasably locking the retainer side members in position across theexposed' ends of the disk.

6. A valve actuating mechanism comprising a rocker arm having a valve stem engaging disk journaled therein, characterized by said arm having a transverse disk receiving recess extending entirely across the same with the ends of the disk exposed at opposite sides of the arm, disk retainer members pivotally mounted on therocker arm and normally positioned across the exposed ends of the disk, and an abutment on one end of the disk engageable with one of said retainer members for limiting rocking motion of the disk in its recess.

'7. A valve actuating mechanism comprising a rocker arm having a valve stem engaging disk journaled therein, characterized by said arm having a disk receiving recess extending entirely across the same with the ends of the disk exposed at opposite sides of the arm, disk retainer means comprising bars carried on the sides of the rocker arm movable to and from positions across the exposed ends of the disk, means for releasably locking said bars in position across the ends of said disk, and means on the disk engageable with said disk retainer means for limiting rocking motion of the disk in its recess.

8. A valve actuating mechanism comprising a rocker arm having a valve stem engaging disk j ournaled therein, characterized by said arm having a disk receiving recess extending entirely across the same with the ends of the disk exposed at opposite sides of the arm, disk retainer means comprising bars carried on the sides of the rocker arm movable to and from positions across the exposed ends of the disk, means for releasably looking said bars in position across the ends of said disk, and a shoulder formed on one end of the disk engageable with one of said retainer bars for limiting rocking motion of the disk in its recess,

9. A valve actuating mechanism comprising a rocker arm having a transverse recess therein and a valve stem engaging disk journaled in said recess characterized by one end of said disk being exposed at the side of the arm, a bar pivotally mounted on the rocker arm and normally positioned across the exposed end of the disk to prevent axial removal of the disk through said side of the arm, and an abutment on said exposed end of the disk engageable with said bar for limiting rocking motion of the disk in its recess.

10. A valve actuating mechanism comprising a rocker arm having a transverse recess therein and a valve stem engaging disk journaled in said recess characterized by one end of said disk being exposed at one side of the arm, a bar pivoted on said side of the arm movable to and from a position across the exposed end of said disk, means releasably locking said bar in position across the exposed end of the disk, and an abutment on the exposed end of the disk engageable with the locked bar for limiting rocking motion of the disk in its recess.

LOUIS R. SPENCER. 

